Many types of machines are used for fitness or sport training. Such machines are already known from their wide market availability for domestic, rehabilitation and commercial purposes. Treadmills, or running machines, are one of the most common forms of such machines. Treadmills typically include a support frame, a deck, an endless belt, a drive mechanism and a user interface. The endless belt typically extends over the deck and rotates around the deck and a pair of substantially parallel rollers to simulate the ground moving beneath a user as he or she walks or runs. The user interface associated with recently existing treadmills typically include a digital electronic control system with embedded software routines. Given the increasing functionality offered by digital electronics it is possible for the control system to store programs for different exercise routines, calorie-burning settings, timings, incline settings, speeds, etc. Users of such machines typically step on to the machine, enter their weight, choice of running program, desired speed or incline etc., and then begin to walk or run with the commencement of the belt's motion.
The belt motion typically ceases when the duration of the selected running program comes to an end, or when the user manually stops the belt by actuating one or more pushbuttons on the control panel. In other existing treadmills, a tether is used to releasably connect the user with the control system of the treadmill. The tether, typically a cord, string or cable, is often connected at a first end to the user and at a second end to the control panel of the treadmill. The length of the tether determines the distance the user can move away from the control panel. If the user moves away from the control panel beyond the predetermined distance, the second end of the tether disconnects from the control panel and the belt motion ceases.
Despite their widespread use, such existing treadmills have a number of drawbacks. Many users have difficulty entering their weight and starting the treadmill quickly. The digital electronic control systems with embedded software routines and increased functionality can sometimes be confusing, or even intimidating, for the user to properly use. Such confusion or intimidation caused by the machine's sophisticated user interface often effectively presents a barrier to widespread use, particularly by the elderly or technologically unsophisticated or those user's which may become embarrassed from their perceived ignorance in public fitness clubs or gymnasia.
For various reasons, such as those discussed above, it is often the case that the user does not enter his or her weight accurately. Consequently, the electronic control system is incapable of accurately calculating such useful information as calories burnt or intensity of training during a workout.
Also, particularly in busy fitness clubs and facilities, it is known that some users will step off the machine during their workout to get a drink, for example, but leave the machine's belt in motion. Whilst the first user is away from the machine it is possible for a second user to step on to the machine's moving belt without realising that the belt is moving. Such instances can also present a safety hazard. Although some existing devices incorporate the use of a tether in order to operate the machine, many find the use of tethers to be difficult to use, restricting, uncomfortable, and otherwise undesirable, and, as such, resist using the safety device. Other instrumentation, such as Linearly Variable Differential Transformers (“LVDTs”) or strain gauges, can be incorporated into a treadmill design in order to detect the presence of a user on the treadmill, or to measure the impact of the user's gate as they run or walk on a machine. However, such instrumentation is typically prohibitively expensive, complex, and impractical to deploy on most commercially available machines for mass market use.
Furthermore, many existing treadmills, particularly those configured for home use, fail to provide sufficient safeguards to prevent the undesired use of the machine by children. The inadvertent actuation of the endless belt by a small child can present a safety hazard.
Additionally, typically exercise machines, such as treadmills, require the user to manually enter or adjust controls on the control or display panel of the exercise machine using the user's hands in order to adjust the speed of the exercise machine, such as the speed of the belt on a treadmill. Such manual action of the user's hand(s) and arm(s) is ergonomically awkward and inconvenient for the user.
Also, the monitoring of the speed and incline of exercise machines, such as treadmills, can be difficult due to the repeated loading of the machine by the user and the vibration generated in response to the operation of the machine by a user. Many existing devices used to monitor speed and incline of exercise machines are expensive, and often exhibit poor durability and reliability.
Thus, there is a continuing need for an exercise machine, such as a treadmill, to automatically detect the presence of a user on the machine in a reliable, cost-efficient manner. It would be advantageous to provide an exercise machine, which can automatically measure the weight of the user without requiring the user to navigate and manually enter his or her weight into the control system of the machine. What is also needed is an exercise machine, which quickly and automatically shuts down when the user leaves the machine. There is also a continuing need for an exercise machine that can readily distinguish between a grown user and a small child and adjust its operation accordingly. A need exists for an exercise machine, such as a treadmill, to automatically vary the speed of the machine (such as the speed of the belt of the treadmill) based upon the speed of the user on the machine without requiring the user to manually input a change in speed using his or her hand(s). What is also needed is sensors which can be used to reliably, effectively and cost-efficiently monitor the speed and/or incline of exercise machines, such as treadmills.